Abstract: When it comes to low profile heatsinks for miniPC/HTPC/MiniITX/bookPCs there aren't many options. With an eye towards the under populated low profile cooling segment, Zalman released
the CNPS8900 Extreme; a 60mm tall, 121mm diameter low profile cooler built for compact cooling situations.

When it comes to low profile heatsinks for
miniPC/HTPC/MiniITX/bookPCs there aren't many options. With an eye towards the under populated low profile cooling segment, Zalman released
the CNPS8900 Extreme; a 60mm tall, 121mm diameter low profile cooler built for
compact cooling situations.

Since I'm
suffering the whims of a sinus clogging flu, I'll just tell you straight up
that Zalman's CNPS8900 Extreme is the best sub-75mm tall low profile
heatsink Frostytech has tested to date. Compared to full fledged heatsinks the CNPS8900 Extreme
is a good-to-average performer, but in this case it's the low profile cooling
capability which dominates.

Based on Zalman's proven "flower
heatsink" design, the CNPS8900 Extreme is an all aluminum heatsink with two 6mm
diameter copper heatpipes conducting heat from the base to the entire
fin circumference. The two looped copper heatpipes and hundreds of aluminum fins
are soldered to a cast aluminum base plate that exposes the heatpipes
to direct contact with a CPUs integrated heatspreader. At the center of the diminutive
60mm tall heatsink is a 110mm PWM fan that operates at 2800-1250RPM
and generates low-to-modest noise.

And no, that
repeated mention of aluminum is not a typo brought on Kleenex
induced coma. The Zalman CNPS8900 Extreme weighs only 400grams, it's aluminum
fins and base plate are heavily copper plated. A little nick with an X-Acto
blade is an easy way to check this sort of thing. :)

The
CNPS8900 Extreme is a suitable low profile heatsink for compact computer cases
and compatible with Intel socket LGA1366/1155/1156/775 and AMD socket
FM1/AM3/AM2 processors. Build quality is first rate, installation
straightforward and the Zalman CNPS8900 Extreme heatsink retails for around $42CDN
/ USD.

Heatsink
performance aside, you've got to hand it to Zalman's thermal engineer for coming
up with such a nice looking cooler. With the internal fan removed we get a
better look at the fin structure and elements of the copper plated cast aluminum
base plate which help relieve hot spots from developing behind the fan motor.

In previous
models based on the flower heatsink design, the fins were the base and heat conduction relied heavily on the
thermal conductivity of copper alone. With the CNPS8900 Extreme, the fins make
relatively little contact with the base plate, perhaps 10mm or so. The bulk of
heat conduction is tasked to twin looped heatpipes which circle the fins at two
points (~82mm diameter and ~112mm diameter).

I'm not sure of the correct technical name for the fan
power cable connector used with the CNPS8900 Extreme. The heatsink has one of
those mini 4-pin PWM cable connectors that are typically found on videocards
along with an adaptor extension which converts it to standard 4-pin PWM fan
header.

The smaller
connector (pictured above) measures 8.5x4.0mm while the full size fan connector
is 10.5x5.8mm. I suppose some miniITX boards feature either of these fan
headers, so that gives added interoperability.

Mounting Method and Hardware

Zalman's
CNPS8900 Extreme heatsink can be installed on Intel socket LGA1366/1155/1156/775
and AMD socket FM1/AM2/AM3 processors. Installation is straightforward, although
you will need access to the back of the motherboard to affix the metal mounting
bracket. For either AMD or Intel processors, a pair of metal brackets attach the
base of the heatsink on either side of the CPU block.

This
heatsink will be tested on FrostyTech's Intel and AMD version of the Mk.II
synthetic thermal temperature test platform, and compared against a couple
hundred reference heatsinks. The whole test methodology is outlined in detail here if you'd like to know what equipment is
used, and the parameters under which the tests are conducted.